Compensating shock absorber



Sept. '26, 1950 l R. coRTEs coMPENsATING snocx ABsoRBER Filed April 6. 1949 2 Sheets-Sheet 1 RENE CORTES R. com-Es COMPENSATING sHocK ABsoRBER sepnzs, 195o File'd April 6, 1949 2 SheetsfSheet 2 3ra/vmbo@ RENE CORTES ATTO R N EY Patented Sept. 26, 1950 COMPENSATING SHOCK ABSORBER Iten Corts, Vina Del Mar, Chile, assigner of sixty per cent to Dario Sainte-Marie, Santiago,

`Chile Application April 6, 1949, Serial No.85,831 s claims. (o1. 267-34) This invention relates in general to shock abl sorbers and in particular to a new type of shock I.absorber having compensating means therein.

An object vof this invention is to -provide a now compensating shock absorber capable of absorbing shocks to a higher degree than shock absorbers heretofore known by utilizing an elastic medium including both steel springs and oil.

A further object of the invention is to provide a shock absorber having'a high rate of absorption of the shock when thesprings have reached a certain position-thus compensating the delayed effects of the original shock.

of a single preferred embodiment of the invention as applied to a motorcycle when taken together with the accompanying drawings, in which:

Fig. 1 is a side elevational view of a shock absorber according to the present invention as applied to the front wheel of a motorcycle;

Fig. 2 is a front elevationalview of the arrangement shown in Fig. 1;

Fig. 3 is a vertical cross sectional view of the shock absorber per se; and

Fig. 4 is a cross sectional view taken on the line A--A of Fig; 3.

The shock absorber of the present invention provides an extremely satisfactory compensating shock absorber mechanism as applied to a motorcycle but it may be adapted to any type of machine where shock absorption is desirable or necessary. The shock absorber disclosed in the drawings generally designated I is shown attached to the iront wheel 2 of a motorcycle partially shown as at 3. The shock absorber yis connected between the axle 4 of the front wheel l2 and a plate 5 comprising a part of the chassis of the motorcycle 3. The wheel 2 of the motorcycle is connected to the chassis of the motorarm 'I in such a manner that the wheel upon :going over a bump will pivot around the pin 8.

The force of the upward movement of the wheel will be transmitted by means of the rods 9, I Il to the shock absorber I which due to the rod II "is prevented from movement by its connection to the plate 5 of the chassis of the motorcycle.

As shown in Figs. 3 and 4 of the drawings theshock absorber I comprises an external cas- Ving I2 having separating walls I3, I4 therein as'at 2U. The threeV cylinders are in communication with one another by means of openings 2I and 22 provided in the partitions I3, I4. The entire casing is lled with oil 0f any suitable l type.

The rods 9, I0 and II actually constitute piston rods which pass through the cover IBjin openings 23, 24 and '25 respectively into the 45 cycle by means of the front struts 6 and a lever `the cylinder wall of the cylinder I'I.

cylinders I5, I'I and I6 respectively. These rods of course are so arranged in the openings in the cover I8 as to prevent the leakage of oil from the cylinders.` YSecured to the ends ofthe piston rods are the piston heads 26, 21 and 28 which t tightly in their respective cylinders. Steel springs 29 and 30 are attached to the cover I8 at one end thereof and to the piston heads 25, 2l at the other ends thereof. A steel spring 9I is attached to the cover I9 at one end thereof and to the piston head 28 at the other end thereof.

The piston 2B has an opening 32 in a side thereof which coincides with a vertical slit 33 cut out of the cylinder wall of the cylinder I5. In like manner the piston 2l has an opening 34 therein coinciding with the vertical slit 35 in A vent 36 is provided with a plug of the usual type for lling the shock absorber with the proper type of oil as commonly utilized in shock absorbers.

The operation of the shock absorber as described above and as applied to a motorcycle will be hereinafter 'described assuming in the first place that the surface over which the vehicle is moving has only small obstacles or bumps to upset the horizonal stability of the chassis of the vehicle. The horizontal stability of such a vehicle is directly proportional to the weight and velocity of the vehicle. In such a case the initial shocks produced are absorbed by the elasticity of springs 29 and 3!! which are directly connected to the rods Il!` and 9 leading to the front axle lI of the machine. The piston heads 26, 2'I will at the same time be movable between the points designated by the dotted lines a and b. Analyzing separately cylinder Il it can be seen-that its internal volume is divided by piston head 2l into two separate chambers indicated as I'Ia and IIb. These chambers, however, are joined by opening 3e `and. the Yslit 35 whereby any difference in the volume of oil contained in the two chambers is compensated `as the piston head 21 slides between a, b. Practically speaking, opening 34 controls the rate of 'l absorption of the springs 30 according to fthe volume of oil which passes through /it/to the compensating. chambers I'Iog, |112/ /The same structural relationship and operation is in cylinwalls of the pistons 26, 21 and therefore the pis--v ton will remain stationary.

If it is presumed that the road surface offers a greater obstacle than in the foregoing description then the springs 29 and 30 are not capable of absorbing the shock in their movement from a to b and the movement will lcontinue-v from b to c. In this case the openings 32, 34 are closed or blocked off by cylinder walls o-f the chambers l5 and ll respectively after point b is passed and the'openings 22, 22 are automatically freedfrom 'the block formed by the pistons 26, 21'.' As'the openings 22, 22 are now free communication is established between the chamber Ilia,l andthe chamber Hb, on the one hand, and between `chamber' Ilia andv |57), on the other'hand,A thus allowing the piston I I' to move' in response tof'the double pressure ofoil acting on the chamber I'b through the openings 2|, 2E' from the adjoining cylinders. As the spring 3| is compressed by this movement the oil in the chamber i6. 'which'is displaced by the piston ZB'passes from the chainber '|6a through the openings 2'2', 22 into the chambers Hb and |517.

The reversal of the foregoing operation occurs as the various pistons return Vor revertV totheir original or normal positions.

The main feature of the present shock absorber is the high rate of absorption of the shock'when the springs 29 and 30 reach their critical point after passing thev point b. The spring 3| then rapidly goes into action thus compensating the delayed eects of the original shock.y The wheel of the machine is also rapidly drawn back. from the obstacle Vin the initial stagesv thereby affecting the stability of the chassis at 5in a` minute or practically non-existent degree. -In order to provide a proper functioning of' this shockabsorber various factors'must be taken into account in its design. These factors are (1) `the weight and average velocity of the vehicle; (2) elasticity of the springs 29, 30 and 3l', the degree of' the powers ofv absorption and elastic movementsI of the rst two springs in relation to the third; (3) the capacity or size of the openings 2|, 22, 32, 34 and the slits 33, 35; (4') Vthe locations of" the openings 22, 32, 34 andthe slits 33, 35; 'Such 'matters can vary in each case' and are'considered to be within the skill of a persony well versed in the art to which the present invention pern talns and these matters inthe iight of the teachingsY of the present application to such a person will be apparent.

Itis to be understood that the shockv absorber as disclosed in the present application and. which has been described as applied tofa'motorcycle is not. limited to a. machine of this type but can -fbe adapted to any typev oi` vehicle or machine including airplanes where Vthe shock absorber `would be particularly beneiicialjasappliedto -a steerable front Wheel.

v VWhat I claim is: v

1. A compensating shock absorber for a vehicle, comprising a casing, partitions in said` casing dividing said' casingv into three parallel cylinders, a piston slidably insertedin each4 saidgcylinders, a rconnecting rod connected to each said 4 piston and extending out of said casing for connecting said shock absorber to said vehicle, a vspringin each said cylinder connected tosaid casing at one end thereof and to said piston in `.said cylinder at the other end thereof, said cas- -ing being completely lled with a liquid medium,

upper and lower passageways in said partitions for connecting said cylinders, two of said pistons having openings through a side wall thereof, two of` said cylinders having slots in a wall thereof for coacting with said openings in said pistons,

jan initial shock from said vehicle being absorbed by said springs and the lower passageways between said cylinders being closed, a larger shock forcing said pistons having the openings therethrough tob'ecorne4 displaced for openingicom munic'ation between said cylinders.'

2.' vcompensating shocky absorber,I for' vehicles comprisingy a casing having internal partitions therein, said partitions dividing said casing into three parallel cylinders, a piston slidably mounted in. each said cylinder, a ccnnectingrod connected to each saidpiston in each said cylinder and extending from said casing for attachment to said'vehicle, a spring in each said cylinder secured to said casingY and to said piston', fluid passage openings in said partitions connecting the central cylinder with contiguous cylinders adjacent the top of said' casing, said partition walls-having lower, openingsA therethrough, said lower openings being normally closed' by theside walls of said pistons in the outer of said cylinders,

'said pistons in said outer cylinders having uid. lpassage openings therethrough, the'side walls of said casing having elongated slots therein for eoacting with said openings in the said-pistons lwhen said 4lower openings in said partitions are prising la casing'having three parallel cylinders therein, upper and lower openings between said cylinders, pistons slidablymounted in saidcylinders and adapted for connection to a vehicle-to lwhich Athe shock absorber is'attached, vineansfin said casing and the outer of said' pistons for equalzing pressure in the chambers formed-in the outer of said cylinders by said pistons,said piston in the central of said cylinders being normally maintained V.stationary by said lower openings being closed but' adapted under high shock conditions to move when said lower openings are exposed by movement of said pistons in theouter of said cylinders. P y,

- RENE CGRITES.v

fREFERENCES CITED The following references are of record in 'file of this parent:

UNITED STATES PATENTS,l

Number NameI v YDate -l 13423-,904 yBlyblll'g v Julyy 25, 1922 FOREIGN PATENTS Number f -Country Date l 25,760 Great Britain i--- Nov. 28,1908 

